A rechargeable secondary battery has been widely used as a large power storage battery for an electric car or a power storage system and a compact, high performance energy source of a portable electronic device such as a mobile phone, a camcorder, and a notebook.
A lithium ion battery as a secondary battery has an advantage of having higher energy density and larger capacity per unit area than a nickel-manganese battery or a nickel-cadmium battery.
However, the lithium ion battery as a next-generation electric car battery has a stability problem by overheating, low energy density of about 360 Wh/kg, low output and the like.
In order to overcome these problems of the lithium ion battery, research and developments for an all-solid Lithium-Sulfur battery and the like, which can embody high output and high energy density, have been actively proceeding.
The all-solid Lithium-Sulfur battery uses sulfur as a positive active material and lithium metal as a negative electrode, and has a theoretical energy density of about 2600 Wh/kg, which is about 7 times higher than the existing lithium ion battery. Thus, it is suitable for a power supply for an electric car.
Further, the all-solid Lithium-Sulfur battery prevents life time characteristic reduction caused by the Lithium-Sulfur compound dissolved in liquid electrolyte, and leaking of the liquid electrolyte and fire at high temperature, as compared to the lithium-sulfur battery using the liquid electrolyte.
However, a volume of the sulfur electrode (positive electrode) changes about 180% as the all-solid Lithium-Sulfur battery being charged and discharged. Thus, there is no contact between the positive active material and the electrolyte, thereby capacity characteristic and life time characteristic decrease.
The existing secondary battery uses nano-sized silicon as a negative material and the like to prevent life time reduction according to the volume change during charging and discharging.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention, and therefore, it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.